Author Topic: Hybrid tank/tankless water heater?  (Read 6346 times)

Cognitive Miser

  • Stubble
  • **
  • Posts: 133
Hybrid tank/tankless water heater?
« on: June 21, 2016, 09:57:33 PM »
We have a new HVAC contractor who also installs water heaters, and ours is about 14 years old. He recommended we get a Rinnai hybrid. At first I thought he was talking about an electric heat pump like the GE Conservation one, but it appears this is a different technology. "Hybrid" in this case is a tank/tankless combo that gives an eye-popping 180 gph of hot water the first hour. It's quite expensive and I'm wondering if anyone here has experience with this sort of product.  If the main benefit is that you get a ton of hot water, but there's no efficiency advantage, I'm not sure it's for us.

The website is not all that helpful in comparing efficiency to other types, or even in describing how it works:
https://www.rinnai.us/hybrid-tank-tankless-water-heater

boarder42

  • Walrus Stache
  • *******
  • Posts: 9332
Re: Hybrid tank/tankless water heater?
« Reply #1 on: June 22, 2016, 06:12:25 AM »
i think this is a spendy pants way to go.  do you need 180gph of hot water?  is your current hot water heater actually needing replaced or is it working fine?  just b/c something has age doesnt mean it needs to be replaced.  i just moved into a house built ni 2004 and everything is original.  my wife likes baths and it has a large soaker tub.  and we only have a 40 gallon water heater.  i had set it to the level of our 2 - 40s at our previous house but it wouldnt fill the tub with hot water.  so i turned it up... the difference in monthly cost is 2 dollars.  not worth buying and installing a new larger water heater before this one dies.  so do you really even need it or are you just being sold something would be my first question.  secondly.  who needs 180gph of hot water.  unless this is a need for you its likely not the most economical solution.

Basenji

  • Handlebar Stache
  • *****
  • Posts: 1031
  • Location: D.C.-ish
Re: Hybrid tank/tankless water heater?
« Reply #2 on: June 22, 2016, 06:21:08 AM »
I love a good bath and have a deep tub. Our water heater can't fill the tub completely with hot water, so I put two big pots of water to boil on the stove and pour them in. Works great, feels old timey. But yeah, if my water heater dies, it will be very hard to resist one of those tankless babies.

Fishindude

  • Magnum Stache
  • ******
  • Posts: 3075
Re: Hybrid tank/tankless water heater?
« Reply #3 on: June 22, 2016, 06:25:57 AM »
I think the tankless ones are a good way to go if building a new place or if your old one craps out on you.
They are more energy efficient because they only heat the water when needed, unlike a tank type which heats the water 24/7.   Some of these require a pretty hefty electric feed, so check that out beforehand.

boarder42

  • Walrus Stache
  • *******
  • Posts: 9332
Re: Hybrid tank/tankless water heater?
« Reply #4 on: June 22, 2016, 06:50:37 AM »
I think the tankless ones are a good way to go if building a new place or if your old one craps out on you.
They are more energy efficient because they only heat the water when needed, unlike a tank type which heats the water 24/7.   Some of these require a pretty hefty electric feed, so check that out beforehand.

I love a good bath and have a deep tub. Our water heater can't fill the tub completely with hot water, so I put two big pots of water to boil on the stove and pour them in. Works great, feels old timey. But yeah, if my water heater dies, it will be very hard to resist one of those tankless babies.

did neither of you read the full post.  its a tankless hybrid meaning it has a tankless and a full tank of heated water along with it.  seems like rampant consumerism to me to have 180gph of hot water

Spork

  • Walrus Stache
  • *******
  • Posts: 5742
    • Spork In The Eye
Re: Hybrid tank/tankless water heater?
« Reply #5 on: June 22, 2016, 07:04:46 AM »
I have a Rinnai tankless (not the hybrid).  While I think it is pretty awesome, I often question whether it pays for itself.  I suspect it is a lifetime "break even".

That said, I've seen people build their own version of this:
* Take your old water heater (assuming the tank is still in good shape), paint it black, put it in a box which is also painted black.  Put that out in a southern exposure and you have a nice solar water heater.  Now... feed THAT thing to a tankless.   It will have to do very little work.


Rightflyer

  • Bristles
  • ***
  • Posts: 392
  • Location: Cotswolds
Re: Hybrid tank/tankless water heater?
« Reply #6 on: June 22, 2016, 07:29:31 AM »
We have a Rinnai.
It does the domestic hot water AND the heating for the house. Even in the dead of winter there is no shortage of hot water.

Now, that said, it does take about 15 minutes to fill the soaker tub, which I would guess is about 60 gallons.

Touch wood, it has performed maintenance free for 4 years.

In our case, I'm not sure having a tank as well would provide any benefit in hot water volume or in efficiency.

Good luck.

RichMoose

  • Pencil Stache
  • ****
  • Posts: 965
  • Location: Alberta
  • RiskManagement
    • The Rich Moose | A Better Canadian Finance Blog
Re: Hybrid tank/tankless water heater?
« Reply #7 on: June 22, 2016, 09:55:30 AM »
We have a new HVAC contractor who also installs water heaters, and ours is about 14 years old. He recommended we get a Rinnai hybrid. At first I thought he was talking about an electric heat pump like the GE Conservation one, but it appears this is a different technology. "Hybrid" in this case is a tank/tankless combo that gives an eye-popping 180 gph of hot water the first hour. It's quite expensive and I'm wondering if anyone here has experience with this sort of product.  If the main benefit is that you get a ton of hot water, but there's no efficiency advantage, I'm not sure it's for us.

The website is not all that helpful in comparing efficiency to other types, or even in describing how it works:
https://www.rinnai.us/hybrid-tank-tankless-water-heater
What is the true lifespan of these? Although 180g is WWAAYYY overkill for what I would ever need, a significant lifespan may justify the additional cost over a regular water tank. Most water tanks last about 10-12 yrs with some adequate maintenance.

Cognitive Miser

  • Stubble
  • **
  • Posts: 133
Re: Hybrid tank/tankless water heater?
« Reply #8 on: June 22, 2016, 10:00:22 AM »
The benefit of the hybrid (which has a 40 gallon tank) is that it only requires a 1/2" gas connection, which is what we have. We can't go tankless because we would have to replace the gas line out to the municipal supply at the street, which would be cost-prohibitive.

We've been in the house for less than 3 years and are not sure how well the prior owner maintained the unit. We are pretty handy but this is our first house and we just learned about the yearly sediment flush - so we haven't been doing that.  We have a baby on the way and I guess we're thinking about a preemptive replacement since we're not sure of the condition of our current unit and don't want to deal with the possibility of an emergency replacement with a newborn (and a finished basement, by the way).

We seem to have enough water out of our 50 gallon unit for our own day-to-day use, but we do run out when we have house guests, which is fairly often.  My in-laws brought their camper instead of staying with us on their last visit, partially for this reason.

I'm not sure we know the "true lifespan" because I think they are a fairly new product.

We did find this unit on Lowe's website and it looks as if our new guy is quoting an additional $2100 to install it.  Probably more, since I assume he can get it at a wholesale price.  I think perhaps we are being taken for a ride...

At least he didn't charge us anything for the A/C troubleshooting, but his associate put seven holes in our drywall trying to find the broken duct.  I am so sick of dealing with service people.
« Last Edit: June 22, 2016, 10:12:43 AM by Cognitive Miser »

RichMoose

  • Pencil Stache
  • ****
  • Posts: 965
  • Location: Alberta
  • RiskManagement
    • The Rich Moose | A Better Canadian Finance Blog
Re: Hybrid tank/tankless water heater?
« Reply #9 on: June 22, 2016, 10:18:46 AM »
We seem to have enough water out of our 50 gallon unit for our own day-to-day use, but we do run out when we have house guests, which is fairly often.  My in-laws brought their camper instead of staying with us on their last visit, partially for this reason.

Sounds like a conventional HWT is the best way to go!

Cognitive Miser

  • Stubble
  • **
  • Posts: 133
Re: Hybrid tank/tankless water heater?
« Reply #10 on: June 22, 2016, 10:31:36 AM »
did neither of you read the full post.  its a tankless hybrid meaning it has a tankless and a full tank of heated water along with it.  seems like rampant consumerism to me to have 180gph of hot water

Haha, thank you boarder.  Yep, it has a tank.  I don't think we need 180 gph, but I don't know how much we need.  He didn't tell us it provided THAT much.  We were thinking a standard 60 gallon tank would work for us until we found out that they are no longer made, since the efficiency standards changed.  We'd have to get a 75 gallon unit, which doesn't currently fit in our space.  It would if we tore down some shelves left by the prior owner.  Sounds like an opportunity to declutter.  I think I will try to sell my husband on a standard 75 gal gas tank DIY.  Or do-it-himself, since I'm pregnant...

Cognitive Miser

  • Stubble
  • **
  • Posts: 133
Re: Hybrid tank/tankless water heater?
« Reply #11 on: June 22, 2016, 12:29:28 PM »
Ooh! I just found this Rheem XR90 which seems similar to the outrageous Rinnai but smaller. 29 gal tank, but with a 90 gal first hour rating and an Energy Star rating.  Can be installed by one person - it only weighs 130 lbs.  On sale for $584 at Home Depot with a $70 state rebate.  Rated for high altitude (Rinnai only rated for 5400 feet and we are at 6000 ft.)

Rheem doesn't call it a "hybrid" but it has a fan-assisted draft inducer which enables it to provide 60k BTU instead of the standard 30k or so.  So it's not a conventional HWT, but uses some electrical power to run the fan.  12 year warranty.  Looks promising.

http://m.homedepot.com/p/Rheem-Performance-Platinum-XR90-29-Gal-Tall-12-Year-60-000-BTU-Natural-Gas-Water-Heater-XG29T12XR60U0/205210739

Basenji

  • Handlebar Stache
  • *****
  • Posts: 1031
  • Location: D.C.-ish
Re: Hybrid tank/tankless water heater?
« Reply #12 on: June 22, 2016, 04:56:23 PM »
Yes I read the post. What I was trying to say and failed to was: don't get an overly large hybrid or traditional or tankless if you only need a bunch of hot water for the occassional bath. We lived in Japan where there were two small  tankless heaters, one for the kitchen and one for the bathroom. Worked great, not sure why you need a tank too. Seems like overkill.

Cognitive Miser

  • Stubble
  • **
  • Posts: 133
Re: Hybrid tank/tankless water heater?
« Reply #13 on: June 22, 2016, 09:03:24 PM »
don't get an overly large hybrid or traditional or tankless if you only need a bunch of hot water for the occassional bath... not sure why you need a tank too. Seems like overkill.

Got it!

Need extra capacity because we like our house guests to be comfortable.  Showers for six adult plus doing breakfast prep and dishes puts quite a strain on our current tank.  Don't want tankless because we don't see value in excavating the front yard to upsize the house gas service line, when there are other options.

Choices

  • Pencil Stache
  • ****
  • Posts: 516
    • ChooseBetterLife
Re: Hybrid tank/tankless water heater?
« Reply #14 on: June 22, 2016, 10:41:58 PM »
My vote is to only get what you need, not more. If you have guests often you might need a higher capacity, but how often do you truly have six people trying to take showers at once?

When your current heater truly stops working, then go for the minimum that will do the job.

Our plumber said that tankless units are great if the owners are conscientious and do the maintenance (flushing once or twice per year). Otherwise, they're prone to problems and early demise. How well do you maintain your appliances?

boarder42

  • Walrus Stache
  • *******
  • Posts: 9332
Re: Hybrid tank/tankless water heater?
« Reply #15 on: June 23, 2016, 05:57:07 AM »
yeah you're not running a hotel.  you dont plan for maximum usage for 10% (probably less) of the year

MMM98

  • Stubble
  • **
  • Posts: 113
Re: Hybrid tank/tankless water heater?
« Reply #16 on: June 26, 2016, 07:56:59 PM »
I have a gas powered tankless.  Two questions were asked, and one should have been asked.

The lifespan is 20 years according to Consumer Reports.  The cost savings is barely measurable.  Most of the energy is used to heat the water in a traditional water heater to to maintain the temp.

The question that should be asked is maintenance.  Depending on your water, annual flushing of the heater is required, like cleaning a coffee pot.  You even use vinegar, you use a pump.